Solar photovoltaic-battery system as a green energy for driven electrochemical wastewater treatment technologies: Application to elimination of Brilliant Blue FCF dye solution

This study investigate the feasibility of using solar photovoltaic cell (PV) – battery system as a renewable energy source for driven electrochemical treatment of acidic solution of food colorant Brilliant Blue FCF (E133) dye using boron-doped diamond (BDD) anode and carbon-felt cathode. The average solar irradiation intensity of over 20,000 kJ m−2 day‒1 was recorded and the PV cells produced more than 10 A current intensity for 8.5–9 h a day, which was sufficient for completely charge two 12 V batteries during the day. Irrespective of slight fluctuation of solar irradiation, constant electric current values (100–500 mA) were able to selected for the electrooxidation with H2O2 (EO-H2O2) and EF treatment of E133 solution. Complete decolorization and mineralization of the E133 solutions was achieved with either process at higher current, whereas only total color removal was obtained at lower current with excellent COD removal. The initial N in the E133 molecule was recovered in the treated solutions mainly as NH4+ along with significant proportion of NO3‒, whereas SO32‒ in the molecule was released into the solution as SO42‒ without detecting SO32‒. The solar PV-battery system is a suitable green energy source for efficient electrochemical treatment of organic polluted wastewater.